1. Field of the Invention
This invention relates to a material handling means and more particularly to a means adapted to grasp and transport relatively flexible cylindrically-shaped objects. Specifically, the instant invention relates to a tire gripper adapted to grasp and transport a first stage green tire by using a plurality of air springs to grip the outer surface of the first stage green tire.
2. Description of the Prior Art
The use of air actuated means to facilitate the gripping of an article is well-known in the art as evidenced by U.S. Pat. No. 3,620,561 to Grotkasten, et al., relating to a tire transporting device having tire engaging members actuated by air cylinders; U.S. Pat. No. 3,809,423 to Gazuit which relates to a tire loader for a tire curing press which is actuated by an air cylinder; U.S. Pat. No. 3,845,979 to Schatz, et al., which discloses a tire handling device having hangers which are adapted to grasp the bead of a tire and are actuated by air cylinders; and U.S. Pat. No. 4,105,486 to Cantarutti which discloses a tire transfer device employing an outer gripping means actuated by air cylinders.
Even further, the use of a flexible, pneumatically expanded member such as a bellows or rubber air bag is well known in the art as evidenced by U.S. Pat. No. 3,056,625 to Timmerman which discloses the use of glands or air bags to displace a pivotally mounted member which is in turn utilized to grasp an article; U.S. Pat. No. 3,967,946 to Campbell which discloses the use of a bellows in connection with a mold holder; U.S. Pat. No. 4,148,681 to Collins, et al., which shows an expansible member utilized for transferring a tread from a first work station to a further work station in a tire building machine; and U.S. Pat. No. 4,254,984 to Abraham, et al., which discloses the use of air bags to actuate a lever system adapted to grasp articles.
Although the above-noted prior art discloses several means for utilizing an expandable member for material handling purposes, the requirements for a material handling device for a first stage single ply radial tire carcass differ substantially from those provided by the prior art means.
Specifically, the first stage green carcass of a single ply radial tire is in the form of a highly flexible cylindrically-shaped member. The highly flexible nature of the first stage tire carcass poses a significant material handling problem that cannot be solved by the prior art. Even further, there is a need for a means for a material handling means which may be used in conjunction with automated equipment and is readily adapted to allow the transfer of the tire carcass from the material handling means to a work station. For instance, in transferring the first stage tire carcass from the material handling means to an universal bladderless drum, it is necessary to cause a slight squaring of the cylindrical configuration of the tire carcass in order to facilitate the slipping of the tire carcass over the drum of the universal bladderless drum machine.
The prior art devices do not disclose any means for providing such a controlled deformation in order to facilitate loading and unloading.
There is, therefore, a need for a means for handling a highly flexible cylindrically-shaped member in such a manner as to allow a slight deformation of the cylindrically-shaped member in order to facilitate the transfer of the cylindrically-shaped member from the material handling means to a work station.
The instant invention solves these problems by providing a means of grasping the highly flexible cylindrically-shaped first stage tire carcass in such a manner as to allow selective deformation of the tire carcass in order to facilitate transfer of the tire carcass between the material handling means and a work station.